Sonos 27.1 is rolling out now. The notable change is that a queue no longer disappears simply because you switch to a radio source or television audio. The app also adds search autocomplete and makes system updates easier to find in settings. That is a small product change with outsized value for anyone who regularly moves between rooms, sources and listening modes.
For a custom Sonos controller, it is also a useful regression test: play a queued album, switch the room to TV or radio, then return to the music source and see what the system reports. Keep the custom controller’s assumptions about queue state separate from the official app’s presentation. Sonos lists iOS app 90.00.47 and Android 90.00.43 for this release; rollout is phased.
Do this: check whether the app update has arrived and test the queue-preservation behavior in one room before changing any custom code.